Balsamic Portabella Mushroom Recipe

Prepare vegetables

Preheat oven to 425°F (220°C). Clean portabella caps by wiping with a damp paper towel and remove stems. Lightly score the tops with a knife (shallow X pattern). Slice the eggplant into 1/2-inch rounds and spread on a sheet pan lined with parchment.

Arrange mushrooms and onions

Place portabella caps gill-side up and the sliced eggplant and red onion on the sheet pan in a single layer so they roast rather than steam.

Make marinade

In a small bowl, whisk together 3 tablespoons olive oil, 4 tablespoons balsamic vinegar, brown sugar (or honey), minced garlic, chopped thyme, kosher salt, and black pepper until sugar dissolves and mixture is emulsified.

Marinate vegetables

Brush or spoon half of the marinade over the portabellas (into the gills), eggplant slices and onion so they are coated. Reserve the remaining half for basting and for finishing the sandwich.

Roast and glaze

Roast vegetables for 15 minutes, then remove from oven, baste with another tablespoon of olive oil and 1 tablespoon balsamic (from reserved marinade) and turn eggplant and onions. Roast an additional 8–12 minutes until eggplant is golden and mushrooms are tender (portabellas should be juicy but not soggy). If desired, broil for 1–2 minutes to develop char—watch closely.

Prepare ciabatta

While vegetables roast, halve ciabatta rolls and spread softened butter lightly on cut sides. Toast cut sides in a skillet over medium heat or under the broiler until golden and crisp, about 2–3 minutes.

Warm goat cheese

Slice or crumble the herb peppercorn goat cheese. If you prefer it softer, warm the cheese briefly in the oven for 2–3 minutes on a small tray so it spreads easily.

Assemble sandwiches

On the bottom halves of the toasted ciabatta, lay a small handful of baby spinach or arugula. Place one roasted portabella cap (or 2 smaller caps) per sandwich, then layer roasted eggplant slices and roasted red pepper strips. Crumble or spread about 3 oz of the goat cheese evenly over the vegetables.

Finish and serve

Drizzle the remaining balsamic (or an extra tablespoon if using) and the last 1 tablespoon olive oil over each sandwich. Scatter torn basil leaves and microgreens on top, and finish with a light sprinkle of coarse sea salt. Close sandwiches with the top ciabatta halves, press lightly, slice in half, and serve warm.